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Diethylaluminum hydride

Triethylaluminum Preparation. Triethyl aluminum [97-93-8], C H Al, can be prepared by a two-step or a one-step process. In the former, aluminum [7429-90-5], Al, powder is added to recycled triethylaluminum and the slurry reacts first with hydrogen [1333-74-0], to produce diethylaluminum hydride [871-27-2], which in the second step reacts with ethylene [74-85-1], to produce triethylaluminum. In the one-step process,... [Pg.455]

However, when (+)-methylneophylphenyltin deuteride, (+)-(56) ([ot] s + 10.7) is kept in the dark mixed with five equivalents of diethylaluminum hydride for ten hours at room temperature in benzene, optically inactive (72) is formed 44). (In the absence of (Et2AlH)2 less than 3 % of (12) is racemized under these conditions). The four-center transition state is therefore very unlikely. [Pg.106]

Partially or fully alkylated metal hydrides Butyllithium, diethylaluminum hydride, triethylbismuth, trimethylaluminum... [Pg.55]

Hydroaluminum of triethylaluminum forms diethylaluminum hydride. A Conoco patent (5) indicates the hydrogenation reaction is catalyzed by titanium and zirconium in the feed aluminum and probably does not occur with ultrapure aluminum. Ethylene readily adds to the resulting diethylaluminum hydride to yield triethylaluminum. [Pg.95]

Effluent from the hydrogenation reactor is depressured to about 400 psig. This level of hydrogen is required to prevent the reverse reaction, diethylaluminum hydride decomposition, which results in plating of aluminum on the process equipment. Product diethylaluminum hydride, unreacted aluminum, and solvent are charged to the ethylation reactor. Ethylene is introduced and undergoes a rapid, exothermic reaction to form triethylaluminum. A tubular reactor with high heat transfer capabilities is required to control this reaction (12). [Pg.98]

The triethylaluminum reaction product is divided into two streams. One stream, 70-75 percent of, the total, is recycled directly to the hydrogenation unit to form additional diethylaluminum hydride. The other stream, 25-30 percent of the total, is the actual product stream. It is first centrifuged to remove the bulk of unreacted aluminum which is recycled to the hydrogenation reactor along with recycle triethylaluminum. Product... [Pg.98]

After that, the reactive mixture is held for 10 hours at 5 MPa. After the synthesis the mixture is cooled, the excess gases are withdrawn and the contents of the autoclave are sampled. In case there is diethylaluminum hydride in the products, they are subjected to additional ethylation by passing ethylene through the reactive mixture at 75 °C and 0.5-1 MPa for 1.5 hours. The mixture from the autoclave is sent into collector 7 and centri-... [Pg.376]

Raw stock ethylene [0.8-1.5% (vol.) of ethane, not more than 0.5% (vol.) of acetylene, not more than 0.5% (vol.) og methane] triethylaluminum [9.4-10.3% (weight) of active aluminum, 4.1-4.5% (weight) of hydroxy compound, the calculated amount of triethylaluminum is 39.6-43.5% (weight), the rest is diethylaluminum hydride]. The diagram of a pilot unit for the continuous production of higher aluminumtrialkyls is given in Fig. 88. [Pg.381]

GB 1 469 014 (Denki Kagaku Kogyo appl. 30.9.1974 J-prior. 28.9.1973). reduction with sodium diethylaluminum hydride ... [Pg.794]

An advantage of this method is that the impurities of a soluble aluminum anode are not included in the refined product. The chemical step (6a), in which the aluminum to be refined is converted to diethylaluminum hydride by reaction with triethylaluminum and hydrogen, is chemoselective for Al. The resulting diethylaluminum hydride is separated by distillation from the aluminum impurities, which remain unreacted. [Pg.189]

Thermal stability of aluminum alkyls is highly dependent upon the ligands bonded to aluminum. For example, triethylaluminum is stable up to about 120 °C (37) and its initial mode of decomposition is by )S-hydride elimination to generate diethyl-aluminum hydride and ethylene (eq 4.20). Diethylaluminum hydride may decompose further to aluminum, hydrogen and two additional equivalents of ethylene (eq 4.21). The overall equation for decomposition is shown in eq 4.22. [Pg.58]

In some cases it has proved possible to isolate both possible cis-trans isomers of dialkyl-l-alkenyl alanes in a pure form. Triethylalane and acetylene yield the m-butenyl compound (cf. Section V,C,2 for infrared spectrum see Fig. 3). Diethylaluminum hydride and 1-butyne, on the other hand, give the fraws-butenyl compound (cf. Section V,B,4 for infrared spectrum see Fig. 4). [Pg.274]

BROMOCHLOROMETHANE (74-97-5) Reacts with diethylaluminum hydride, diketene. chemically active metals powdered aluminum, calcium, magnesium, zinc. Liquid attacks some plastics, rubber, and coatings. [Pg.200]

BROMURE d ETHYLE (French) (74-96-4) Forms explosive mixture with air (flash point —4°F/—20°C). Hydrolyzes in water, forming hydrogen bromide. Contact with oxidizers, diethylaluminum hydride, chemically active metals aluminum, magnesium, or zinc powders lithium, potassium, sodium may cause fire or explosions. Incompatible with alcohols, diketene. Attacks some plastic, rubber, and coatings. [Pg.204]

Similarly, the useful liquid reducing agent, diethylaluminum hydride, can be readily made by heating triethylaluminum with hydrogen under pressure ... [Pg.91]


See other pages where Diethylaluminum hydride is mentioned: [Pg.309]    [Pg.276]    [Pg.61]    [Pg.247]    [Pg.51]    [Pg.576]    [Pg.576]    [Pg.375]    [Pg.375]    [Pg.3]    [Pg.185]    [Pg.189]    [Pg.189]    [Pg.200]    [Pg.414]    [Pg.518]    [Pg.300]    [Pg.155]    [Pg.155]    [Pg.238]    [Pg.700]    [Pg.414]    [Pg.414]    [Pg.74]    [Pg.74]    [Pg.195]    [Pg.811]    [Pg.51]   
See also in sourсe #XX -- [ Pg.93 ]

See also in sourсe #XX -- [ Pg.811 ]

See also in sourсe #XX -- [ Pg.15 , Pg.304 , Pg.305 ]




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